Controlling Oscillators
This disclosure relates to controlling an oscillator based on a measurement of a frequency reference. A controller determines a control value to control the oscillator based on multiple error values. Each error value is indicative of a measurement of a frequency difference between the oscillator and a frequency reference over a period of time. The determination of the error value is further based on an application time value indicative of a time of application of the control value to the oscillator. Since the control value is based on the application time the controller can compensate for inaccuracies arising from both evolution of the oscillator between measurements and applying the correction at a later time after the measurement. Further, since the multiple error values represent a frequency difference over different periods of time, the controller can compensate for wide range of statistical effects.
Much More than Average Length Specification
- Claim CLM-00001. 1. A computer implemented method for controlling an oscillator, the method comprising:
determining a first statistical correlation between multiple error values, each error value being indicative of a measurement of a frequency difference between the oscillator and a frequency reference over a period of time, and determining a control value to control the oscillator by maximising a second statistical correlation between a frequency difference at a time of application of the control value to the oscillator and a correction caused by the application of the control value, the frequency difference being a statistical variable estimated based on the first statistical correlation and an application time value indicative of the time of application of the control value to the oscillator.
- Claim CLM-00014. 14. A computer system for controlling an oscillator, the computer system comprising:
an input port to receive multiple error values, each error value being indicative of a measurement of a frequency difference between the oscillator and a frequency reference over a period of time; and a processor
to determine a first statistical correlation between the multiple error values; and
to determine a control value to control the oscillator by maximising a second statistical correlation between a frequency difference at the time of application of the control value to the oscillator and a correction caused by the application of the control value, the frequency difference being a statistical variable estimated based on the first statistical correlation and an application time value indicative of the time of application of the control value to the oscillator.
- Claim CLM-00015. 15. A method for generating a clock signal, the method comprising:
generating the clock signal based on oscillations of an oscillator; performing multiple measurements of a frequency difference between the oscillator and a frequency reference over a period of time; determining multiple error values such that each error value is indicative of one of the multiple measurements; determining a first statistical correlation between the multiple error values; determining a control value to control the oscillator by maximising a second statistical correlation between a frequency difference at a time of application of the control value to the oscillator and a correction caused by the application of the control value, the frequency difference being a statistical variable estimated based on the first statistical correlation and an application time value indicative of the time of application of the control value to the oscillator; and applying the control value to the oscillator at the time of application.
- Claim CLM-00017. 17. A clock comprising:
an oscillator and a detector to generate a clock signal based on oscillations of the oscillator; a frequency reference; a measurement system
to perform multiple measurements of a frequency difference between the oscillator and the frequency reference over a period of time; and
a processor
to determine multiple error values such that each error value is indicative of one of the multiple measurements;
to determine a first statistical correlation between the multiple error values;
to determine a control value to control the oscillator by maximising a second statistical correlation between a frequency difference at a time of application of the control value to the oscillator and a correction caused by the application of the control value, the frequency difference being a statistical variable estimated based on the first statistical correlation and an application time value indicative of the time of application of the control value to the oscillator; and
to apply the control value to the oscillator at the time of application.
